Press for a dental flask



June 29, 1965 s. HARRIS PRESS FOR A DENTAL FLASK Filed July 20, 1962 E a i IN V EN TOR. SAMUEL HARRIS 27 I A RNEY United States. Patent Ofi 3,191,226 Patented June 29, 1965 3,191,226 PRESS FOR A DENTAL FLASK Samuel Harris, 94-15 69th Ave., Forest Hills, N.Y. Filed July 20, 1962, Ser. No. 211,333 2 Claims. (Cl. 185.7)

This invention relates to a press for a dental flask wherein artificial dentures are formed and more particularly to a press for a three member hinged molding flask that is especially adapted for processing acrylic teeth to extensive metal bridgework.

A three member hinged dent-a1 flask of the type with which the press of the present invention is to be used is disclosed in my earlier patent, No. 2,896,259 issued July 28, 1959. In the flask therein disclosed there is provided a shell-like base member that accommodates a convex platform piece over which investment material is placed. A metal dental bridge having wax teeth formed thereon in the places where acrylic teeth are ultimately to be provided is arched over, and embedded in the convex surface of the investment material. An upper flask member hinged to one end of the base member is filled with investment material whereupon it is pivoted into engagement with one half of the bridgework embedded in the investment material formed on the platform. A second upper flask member hinged to the other end of the base member is similarly filled with investment material and pivoted into engagement with the other half of the embedded bridgework. After the investment material has hardened and the flask opened, an impression of the wax teeth is formed in the investment material of the upper flask members. The wax can then be melted from the metal bridgework and a mold is thus provided into which acrylic material is placed. By reclosing and tightening the flask the acrylic material in the form of teeth conforming to the pattern of the mold is adhered to the metal bridgework. The flask containing the acrylic material is then placed in an oven and baked to complete the process of forming an artificial dental bridge.

In the process of forming teeth in the mold, plastic acrylic material is placed in the mold cavity and the flask closed and tightened. Excess material is squeezed out of the mold cavity preventing the flask from being completely closed whereupon the flask is opened and the excess material is removed. The flask is again closed and tightened and additional excess acrylic material is squeezed out of the mold cavity. This also is removed and the process repeated until a dense set of teeth is formed. The operator knows when this result has been achieved by the fact that the flask closes completely under the closing pressure and no excess material is squeezed out of the mold cavity.

It should be obvious from the foregoing description of the method of forming dental bridges that it is extremely important to provide means to exert a tremendous force to close the flask and squeeze excess material out of the mold cavity. While the clamping device disclosed in the aforementioned patent has been satisfactory in use, even better dental bridges could be obtained by the provision of an improved clamping device or press. The better dental bridges would not only have denser teeth but more importantly would show a greater fidelity of the finished teeth to all the subtle markings or lines formed in the mold by the wax pattern.

To be acceptable to the dental technician who uses the flask and clamping device or press, the latter must not only achieve its intended purpose but it must also be easy to use, not cumbersome, relatively light in weight and comparatively economical.

Accordingly, it is an object of the present invention to provide, for a three member hinged dental flask, an improved clamping device or press that meets the foregoing criteria.

In carrying out the invention there is provided a press having a base, a first pressure member pivotally connected to the base, a second pressure member pivotally connected to the base and means for urging said pressure members about their respective pivots into engagement with a three member hinged dental flask placed on the base.

Features and advantages of this invention will be gained from the foregoing and from the description of a pre ferred embodiment thereof which follows.

In the drawings:

FIGURE 1 is a front elevation, partly in section, showing a three member hinged dental flask in position in the improved press; and

FIGURE 2 is a side elevation of the same.

Referring to the drawings, a three member hinged dental flask 10, comprising a base member 11, a first upper flask member 12 pivotally connected by a pin 13 to one end of member 11 and a second upper flask member 14 pivotally connected by a pin 15 to the other end of member 11, is shown in operative position in the improved press 16.

The press is illustrated comprising base 17 which generally is narrower than the flask it is designed to hold but the bottom part 18 of which is bowed in its central portion to provide a substantial support for the flask. One end of the base terminates in an upstanding flange 20 which is integral with two spaced apart hubs 21. The hubs are drilled to accommodate a pin 22 that serves as a pivot point for pressure members later to be described. Ribs 23 are provided extending from the bottom of the base to the hubs to trengthen the structure. While the hubs 21 for the pivot pin 22 are shown preferably on the upstanding flanges in a position above the ends of a flask 10 positioned in the press it is to be understood that the pivot point could be located otherwise, even aligned with the bottom part 18 of the base. The other end of base 17 is similarly provided with an upstanding flange 23 terminating in spaced apart hubs 24 that serve to support a pivot pin 25.

A first pressure member 26 is shown having an arm 27 through which pin 22 extends so that the member can be pivoted about the pin. The arm is arcuately shaped to conform substantially to the outline of a flask 10 placed in the press and is provided with a platen 28 which engages a flask member 12 when the press is in use. The arm is also formed with a block-like element 30 that has a slot31 cut therein. A second pressure member 32 similar to member 26 is provided for pivotal movement at the other end of base 17. Thus, member 30 has an arm 33 through which pin 25 extends to provide a pivot for the arm. The arm is formed with a platen 34 and a blocklike element 35 through which a slot 36 extends.

In operation, the press is opened with member 26 pivoted backwardly and resting on edge 40 of flange 20 and member 32 pivoted backwardly and resting on edge 41 of flange 23. The flask 10 is then placed in the press, resting on base 17. It might be noted at this point that flasks differing somewhat from the one disclosed in the aforementioned patent might be used in the present press. Pressure member 26 is now pivoted clockwise until platen 28 rests on the upper flask member 12. Pressure member 32 is pivoted counter clockwise until platen 34 comes to rest on flask member 14. Now a threaded rod 42 is laid in slots 31 and 36 of the two pressure members. A pair of washers 43 and 44 are placed on the rod to provide a bearing surface for nuts 45 and 46 respectively. A pair of wrenches 47, which may preferably be ratchet-type box wrenches, only one of which is shown, are provided to draw the two nuts 45 and 46 together. In so doing the pressure members 26 and 32 tightly close the upper flask members of the three member hinged flask.

Inasmuch as many apparently different embodiments of the invention can be madewithout departing from its spirit or scope, it is intended that what has been shown in the drawing and described in the specification be inter preted. as illustrative and not in a limiting sense.

What is claimed is: v a 1. The combination with a hinged dental flask having an elongated base member, a first arcuate shaped upper flask member pivotally connected to said base member, and a second arcuate shaped upper flask member pivotally connected to said base member, of a press adapted toencircle a closed flask longitudinally in a vertical planei comprising a bottom support member on which said flask is placed, a first pressure member arcuately shaped to conform substantially to said first flask member and pivotally connected to one end of said support member for contact flask member and pivotally connected to the other end of said support for contact withrsaid second flask member, and means for urging said pressure members about their pivots into clampingrrelationship with the dental flask with said first flask member, a second pressure member arcuately shaped to conform substantially to said second placed therein.

2. The combination accordingtto claim 1 wherein the bottom support member is integrally. formed with two upstanding flanges; one at either end thereof, to which the pressure members are pivotally connected, said flanges being spaced apart a distance slightly greater than the length of the closed flask and curving inwardly towards each other so as to'overlap a flask placed therebetween.

' References Cited by theExaminer V UNITED STATES ENTS i 7 207,656 9/78" Haines 18-32 XR 2,896,259 7/59 "Harris 18-33 MICHAEL v. BRINDISI, Primary Examiner. 

1. THE COMBINATION WITH A HINGED DENTAL FLASK HAVING AN ELONGATED BASE MEMBER, A FIRST ACTUATE SHAPED UPPER FLASK MEMBER PIVOTALLY CONNECTED TO SAID BASE MEMBER, AND A SECOND ARCUATE SHAPED UPPER FLASK MEMBER PIVOTALLY CONNECTED TO SAID BASE MEMBER, OF A PRESS ADAPTED TO ENCIRCLE A CLOSED FLASK LONGITUDINALLY IN A VERTICAL PLANE COMPRISING A BOTTOM SUPPORT MEMBER ON WHICH SAID FLASK IS PLACED, A FIRST PRESSURE MEMBER ARCUATELY SHAPED TO CONFORM SUBSTANTIALLY TO SAID FIRST FLASK MEMBER AND PIVOTALLY CONNECTED TO ONE END OF SAID SUPPORT MEMBER FOR CONTACT WITH SAID FIRST FLASK MEMBER, A SECOND PRESSURE MEMBER ARCUATELY SHAPED TO CONFORM SUBSTANTIALLY TO SAID SECOND FLASK MEMBER AND PIVOTALLY CONNECTED TO THE OTHER END OF SAID SUPPORT FOR CONTACT WITH SAID SECOND FLASK MEMBER, AND MEANS FOR URGING SAID PRESSURE MEMBERS ABOUT THEIR PIVOTS INTO CLAMPING RELATIONSHIP WITH THE DENTAL FLASK PLACED THEREIN. 